Evaluation metric. For datasets in Referit3D [1]} (e.g. Nr3D, Sr3D, and Sr3D+), the proposals are generated from the ground truth. The models are evaluated by the accuracy, which measures the percentage of successful matches between the predicted proposal and the ground truth proposal. For ScanRefer [2]}, the proposals are generated from a pre-trained detector. We adopt PointGroup [3]} as the detector, following InstanceRefer [4]}. The Acc@\(m\) IoU is adopted as the evaluation metric, where \(m\text{IoU} \in \lbrace 0.25, 0.5\rbrace \) . Acc@\(m\) IoU measures the fraction of language queries whose predicted box overlaps the ground truth box with 3D intersection over the union (IoU) higher than \(m\) .
